The present invention relates to an electric sewing machine.
It is generally known that the electric sewing machine may be started, stopped and controlled as to the drive speed (stitching speed) by operation of a lever or a foot controller which is connected to the machine body. Further it is generally known that the foot controller may be cordless to control the sewing machine by wireless as disclosed, for example, in the Japanese patent No. 2722769.
However in case the wireless controller is used, troubles may be caused due to outer noises or wrong operation of the wireless controller by a machine operator.
For example, the sewing machine may be caused to start in case the wireless controller is carelessly treaded on by foot while the machine operator is threading the machine needle or setting a cloth under the machine needle. Further, the wireless controller, which is physically independent from the machine body, may produce a start signal in case something is placed on the wireless controller at a place spaced from the machine body.
Further, the wireless controller may be influenced by the signals of other appliances. Generally in the house, there are various electric waves of different frequencies and the infrared rays as produced from the remote control of television, video and so on. The wireless controller may be wrong operated by such signals. Such wrong operation may be prevented by an ID which may be designated to the wireless controller such that the ID may be acknowledged only by a definite signal to make effective the wireless controller. It is, however, actually something troublesome to initialize the ID, the initialization being required each time the wireless controller is exchanged. Further it is troublesome to change or charge the battery as a power source of the wireless controller.
It is, therefore, the object of the invention to solve the various problems which may be caused in case the wireless controller is used in connection with the sewing machine.